Residual Mitral Regurgitation Outweighs Mean Pressure Gradient in Predicting Long-Term Survival After Transcatheter Edge-to-Edge Repair Across Mitral Regurgitation Etiologies.

Background: The influence of elevated mitral mean pressure gradient (MPG) following transcatheter edge-to-edge repair (TEER) on survival across mitral regurgitation (MR) etiologies is controversial.

Aims: To evaluate the impact of MPG and residual MR on survival following TEER.

Methods: In the MITRA-PRO registry survival was assessed three years after mitral TEER for patients with functional (FMR) or degenerative mitral regurgitation (DMR) and MPG < 5 mmHg or ≥ 5 mmHg in the presence or absence of relevant residual MR.

Results: In the MPG < 5 mmHg group 720 patients with FMR were included (57.4%), while 125 patients with MPG ≥ 5 mmHg had FMR (54.1%). 358 patients were identified with MPG < 5 mmHg and 70 patients with MPG ≥ 5 mmHg (16.4%) post TEER in DMR. Only 11 patients had MPG ≥ 7 mmHg. In both FMR and DMR 3-year mortality was not significantly higher in the MPG ≥ 5 mmHg group compared to MPG < 5 mmHg. An analysis with MPG groups (<3; 3; 4; 5; >5 mmHg) demonstrated no increment in 3-year mortality over MPG groups for FMR and DMR. For both groups, residual MR was the main predictor of 3-year mortality, while elevated MPG did not negatively affect survival. Independent of MR entity, the lowest mortality was found without relevant residual MR. In atrial functional MR 3-year mortality was also comparable between MPG < 5 and MPG ≥ 5 mmHg.

Conclusions: An increased MPG of 5-6 mmHg in patients without relevant residual MR did not lead to an increased mortality rate across all MR entities, demonstrating the pivotal role of residual MR for survival following TEER.

Trial registration: DRKS00012288.